Studer OnAir 1500 Operating Instructions Manual page 317

OnAir Digital Mixing Consoles
Example 3 - Emulating an RS Flip-Flop
6-98 Configuration
An RS flip-flop is a logic element that has two stable logic output states (on
and off) controlled by two different inputs; one of them (S) is used to set the
output (Q), the second (R) to reset it (hence the name). It can be composed, for
example, from a pair of cross-coupled logic NOR gates, but is also available
in integrated form (e.g. as TTL or CMOS ICs). Usually the output signal is
available both non-inverted (Q) and inverted (Q). The diagram below shows
an RS flip-flop circuit. The outputs (Q and Q) both change their state on the
rising edge of the R and S inputs.
R
S
Since feedback connections are not allowed within Custom Logic, a configu-
ration as the one suggested below is recommended.
GPInputFunction 32
(Fader Start CDR 2)
GPOutputFunction 31
(Fader Start CDR 1)
In our example, we have two GP output functions, such as the fader start of
two CD players (GP output functions 31 and 32). We want to use them as S
and R signals for our flip-flop emulation.
Step 1
Configure two GP input functions (nos. 30 and 31 in our example) as User-
Key. Set their Source to GPOutputFunction 31 and GPOutputFunction
32. Set their no. 1 arguments to Funct 1. Define Action as set only high
for one, and as set only low for the second one. Set both TriggeredEdge
SW V6.0
Q
Q
GPInputFunction 31
UserKey, Funct 1
R
Set Only Low
Rising Edge
GPInputFunction 30
UserKey, Funct 1
S
Set Only High
Rising Edge
GPOutputFunction 30
UserKey, Funct 1
NOT
1
Document generated: 06.08.14
Q
Q